What are Twitter Trends
Twitter, being a social platform, gives equal freedom to people from all parts of the world to express their thoughts.
These thoughts, expressed in the form of tweets can be analysed to make sense of the mood of the people.
During popular events like Oscars, world cup, etc., people tweet their thoughts about these topics.
Clever algorithms pick up what people are tweeting about from different regions of the world and sum them up in terms of Twitter Trends.
Twitter has some useful information about Trends.
Since Twitter trends are realtime, it's not possible to view topics that were trending a few hours ago on Twitter website. An easy solution to that is Trends24 - a website that provides a quick view of the trending topics for the last 24 hours, for 450+ locations around the world.